Experts and activists appearing before a congressional committee have urged President Bush to take stronger action to pressure the Sudanese government to comply with international demands for a 20,000 - strong United Nations and African peacekeeping force for Darfur. VOA's Dan Robinson reports, the calls follow the president's warning to Khartoum that the U.S. will tighten financial and other sanctions if more progress is not forthcoming.

John Prendergast of the International Crisis Group says the U.S. must begin a new diplomatic offensive on Darfur, and combine it with planning for possible military steps, such as imposing a no-fly zone in Darfur.

President Bush's special envoy for Sudan, Andrew Natsios, has been engaged since his appointment in negotiations with officials and leaders in Khartoum, and with various rebel factions.

Prendergast says this, along with occasional visits by high level officials, such as Deputy Secretary of State John Negroponte who visited Darfur recently, is not enough.

He says the president needs "a full-time diplomatic team" working to, among other things, strengthen the Darfur Peace Agreement, address the affects of the Darfur conflict on Chad and Central African Republic, and save the fragile Comprehensive Peace Agreement that ended the north-south Sudan conflict.

President Bush warned Khartoum this week that the U.S. will tighten sanctions, including blocking dollar transactions, banning Sudanese companies from doing business in the U.S, and targeting specific Sudanese figures known to have had a role in violence against civilians in Darfur.

However, the president agreed to delay implementation of sanctions at the request of U.N. Secretary General Ban Ki-moon.

Describing the president's speech as "bark with no bite" Prendergast says financial and legal measures must be accompanied by planning for stronger steps:

"While we are escalating on the legal and financial measures, we need to plan the military measures," said John Prendergast. "It is very grave to talk about a no-fly zone, it is an act of war because it would involve destroying the air force of the Sudanese regime, we may well need to do that. I think we ought to try these other instruments first, very rapidly, while we plan a credible military effort."

Tom Lantos (file photo)

Lantos says Khartoum's agreement to allow a 3,000 - strong U.N. force join African Union peacekeepers is a sign of progress, but calls the more substantial deployment sought by the international community essential.

Referring to President Bush's decision to delay tightening of sanctions, the lawmaker had this message:

"I want to serve notice on the President of the United States that while we can go along with two or three weeks of delay, this committee and this Congress will not rest any longer and we are demanding action," said Lantos.

Meanwhile, Alex de Waal, director of the Social Science Research Council at Harvard University, says the international community must act to strengthen the Darfur Peace Agreement, implementation of which he describes as "farcical", as well as the wider Comprehensive Peace Agreement for Sudan:

"A Darfur Peace Agreement only makes sense if there is a comprehensive peace agreement that is working and has the confidence of the Sudanese people," noted Alex de Waal. "If the Darfurians see the CPA as a ceiling on their ambition, or worse still as a sinking ship, they have absolutely no reason to join it."

At Thursday's hearing, Mia Farrow, actress and Goodwill Ambassador for UNICEF, said that while non-government aid organizations are managing to save lives in Darfur, despite obstacles from Khartoum, the situation is precarious:

"It is true that they are sustaining the lives of more than four million people," she said. "It is also true that they are hanging by the thread."

John Holmes inspects a water pump in the Es Sallam refugee camp, northern Darfur, 25 Mar 2007

"We do need effective international pressure," said John Holmes. "And we need, I think what would be really helpful, is to have a unified international drive to this, so that it's not distracted by internal divisions, and I'm not going to single out any countries. You all know what I'm talking about. But I think it would be very helpful if we could have a little bit more of a unified position within the Security Council on some of these issues."

Holmes called for a new diplomatic push during the delay that President Bush agreed to at the request of U.N. Secretary General Ban Ki-moon.